If you could accept the limitation that the robot must be able to "see" the beacon, a simple bright light, IR would be my choice, as beacon and a Wiimote "camera" on the robot as sensor would be a very "do-able" answer. Use Google on "wiimote pixart"...

I'm trying to make a three wheeled robot travel horizontally to a transmitter. I was thinking about having it follow a radio signal (transmitter). Meaning that if I had the radio signal on my person, it would be able to follow me as long as I was on fairly flat ground. I would also like it to keep a good distance from the transmitter. As you may already know, I do not know much about robotics but I would like to know what books/sites/parts I can use to make this a possibility.

I was reading a good deal about Directional Finding (DF) hardware. Though I am still not sure how to code or do anything with the parts. I have found this website so far:

Your problem isn't really one of telemetry (unless both you and your robot are equipped with GPS), but of knowing what the strength of the radio signal is.Few cheap radio modules provide this information.

"Pete, it's a fool looks for logic in the chambers of the human heart." Ulysses Everett McGill.Do not send technical questions via personal messaging - they will be ignored.

I think trying to home in on a RF signal is pretty much a non-starter as the needed antenna directionality and required precision of receive signal strength would not be cost or size efficient. IR or ultrasonic detection on a scanning head of the robot would probably be a more practical method.

I'm trying to make a robot that can keep up with a person who is running. Will an IR Sensors/Ultrasonic sensors be able to do that? Does that mean the person running should be carrying something that emits ultrasonic sounds?

Even Kevin Warwick went for IR when he was going to run a half marathon with one of his robots.Unfortunately, on the morning of the race, the robot locked on the strongest source of IR and set out for it.It didn't manage to achieve escape velocity (I don't think the batteries would have lasted until it reached the Sun anyway) and crashed on the other side of the car park.

"Pete, it's a fool looks for logic in the chambers of the human heart." Ulysses Everett McGill.Do not send technical questions via personal messaging - they will be ignored.

Don't take this the wrong way, but your goal is well beyond the means of an admitted robotics novice.

That's not to say it's a goal you shouldn't have, but it may be better if it was a long term with a series of intermediate goals leading up to it.

For example, just getting a three wheeled robot fully controlled by a microcontroller is a substantial task for a novice. You're asking for a list of parts to perform RF location, but what parts are you using to drive the bot? You have motors and a motor controller picked out? Will you be using encoders or an IMU for tracking bot movement (or even better, both)? What method of steering will you be employing? There are a whole slew of questions and issues that will need to be answered and resolved just accomplishing this relatively basic robotic goal.

Your original post was analogous to a high school biology student asking his teacher how to do major surgery.

I'm not trying to discourage you, just trying to get you to understand the scope of your goal.

I understand the scope of my goal. I have about 5/6's of a year to complete it. Does that mean there are no books pertaining to the specific manipulation of RF signals to have a robot follow a transmitter?

While I agree with the "this may be a bridge too far" remarks above, I also know the feeling of wanting to do something I "can't", and have spent happy hours not getting where I wanted to go.

And so, in that spirit...

Maybe "the answer", if you really want to go the RF route, is a highly directional RF receiving antenna (do they exist?) mounted to rotate, a bit like a radar dish... hmm **R**adar.... and use a combination of signal strength and antenna's direction to generate the wanted info?

But all of that from someone who knows nothing about radio, it must be said.

Of course that approach depends on the receiver giving a signal STRENGTH indicatoin, which previous posters have said will be difficult.

To use one of those would entail yet more complexity (=ways to go wrong, be slow)

You'd set the sender to send a square wave of a set frequency. And then "ask" the receiver: "Are you seeing that frequency, or not?" If seeing frequency, antenna is pointed towards sender. If not, not.

Of course, that "solution" assumes that there will be no reflections of the sender's signal off of, say, a wall....

I understand the scope of my goal. I have about 5/6's of a year to complete it.

So if you have less than a year to complete it I would suggest to you that you do not understand the scope of what is involved.

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Does that mean there are no books pertaining to the specific manipulation of RF signals to have a robot follow a transmitter?

I suspect you are right here.

Direction finding with RF is tricky with a skilled operator and practically imposable for a hobby style robot. The RF receiver needed is quite complex, requiring multiple antenna and a phased array. I did see a circuit that used 16 quarter wave dipoles arranged in a circle and switched rapidly round each of them. Then it used a Doppler shift measurement to determine which of the 16 antennas was pointing closest to the transmitter. The circle need to be at least a quarter wavelength in diameter. That makes it a big robot for a simple RF transmitter (450MHz).